A new approach has shown promising results against glioblastoma (the most aggressive form of brain cancer) by using a noninvasive nasal delivery system to activate immune responses inside the brain.
Researchers from Washington University in St. Louis and collaborators in Japan have developed a nasal spray-like therapy that can kill brain tumors without surgery.
The method is designed to overcome two major challenges in brain cancer treatment: the blood-brain barrier and the tumor’s ability to suppress immune activity.
The team engineered STING-activating compounds into nanoparticle-based structures known as spherical nucleic acids, which are stabilized around gold particles. This design protects the molecules from breaking down and enables them to reach the brain through the nasal pathway.
In mouse studies published in the Proceedings of the National Academy of Sciences (PNAS) in 2025, the treatment triggered a strong immune response against tumors and slowed glioblastoma growth.
While the results are encouraging, the therapy has only been tested in animals so far. Researchers say human clinical trials will be needed before any potential medical use, though the approach could eventually be combined with existing immunotherapy drugs to improve effectiveness.
It is still a promising step toward noninvasive brain cancer treatment, but remains at an early experimental stage.
